Multiple-input and multiple-output (MIMO) is a method for increasing the capacity of a radio link using multiple transmit and receive antennas to exploit multipath propagation. MIMO techniques are now in use for many wireless communication standards including IEEE 802.11n (Wi-Fi), IEEE 802.11ac (Wi-Fi), HSPA+(3G), WiMAX (4G), and Long Term Evolution (LTE) (4G). MIMO methods have also been applied and proposed to other uses where multipath is possible, such as power-line communication as per the ITU G.hn standard, the HomePlug AV2 specification and certain Bluetooth environments.